a = int(input())
ans = a >= 30 and 'Yes' or 'No'
print(ans) a = int(input()) a int(input()) int input() input ans = a >= 30 and 'Yes' or 'No' ans a >= 30 and 'Yes' or 'No' a >= 30 and 'Yes' a >= 30 a 30 'Yes' 'No' print(ans) print ans a = int(input()) int(input()) a ans = a >= 30 and 'Yes' or 'No' a >= 30 and 'Yes' or 'No' ans
a = int(input())
ans = a >= 30 and 'Yes' or 'No'
print(ans)